Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
boddi
←
Breton
beuziñ
(cognate)
←
Proto-Celtic
*bādīti
(inherited)
←
Irish
báigh
(cognate)
←
Cornish
beudhi
(cognate)